Expandable thoracic access port

ABSTRACT

A surgical access assembly for positioning within an opening in tissue including an outer member positionable outside a patient and defining an opening therein to receive a surgical instrument. The outer member has a first portion and a second portion wherein at least one of the first and second portions is movable with respect to the other portion. The assembly also includes an inner member positionable within a patient and a flexible member extending between the inner member and outer member, wherein movement of one of the first and second portions of the outer member adjusts tension on the flexible member to retract tissue. A locking mechanism locks the outer member in a plurality of select expanded positions. The locking mechanism includes first engagement structure on the first portion engageable with the second portion and a slidable member movable to a locking position to retain the first and second portions in the select expanded position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.13/166,878, filed on Jun. 23, 2011, which claims the benefit of, andpriority to, U.S. Provisional Patent Application Ser. No. 61/372,939,filed on Aug. 12, 2010, now expired, the entire content of eachapplication being incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates generally to devices and techniques forperforming surgical procedures. More particularly, the presentdisclosure relates to an expandable access device for minimally invasivesurgery.

2. Background of the Related Art

In an effort to reduce trauma and recovery time, many surgicalprocedures are performed through small openings in the skin, such as anincision or a natural body orifice. For example, these proceduresinclude laparoscopic procedures, which are generally performed withinthe confines of a patient's abdomen, and thoracic procedures, which aregenerally performed within a patient's chest cavity.

Specific surgical instruments have been developed for use during suchminimally invasive surgical procedures. These surgical instrumentstypically include an elongated shaft with operative structure positionedat a distal end thereof, such as graspers, clip appliers, specimenretrieval bags, etc.

During minimally invasive procedures, the clinician creates an openingin the patient's body wall, oftentimes by using an obturator or trocar,and thereafter positions an access assembly within the opening. Theaccess assembly includes a passageway extending therethrough to receiveone or more of the above-mentioned surgical instruments for positioningwithin the internal work site, e.g. the body cavity.

During minimally invasive thoracic procedures, an access assembly isgenerally inserted into a space located between the patient's adjacentribs that is known as the intercostal space, and then surgicalinstruments can be inserted into the internal work site through thepassageway in the access assembly.

In the interests of facilitating visualization, the introduction ofcertain surgical instruments, and/or the removal of tissue specimensduring minimally invasive thoracic procedures, it may be desirable tospread the tissue adjacent the ribs defining the intercostal space.Additionally, during these procedures, firm, reliable placement of theaccess assembly is desirable to allow the access assembly to withstandforces that are applied during manipulation of the instrument(s)inserted therethrough. However, reducing patient trauma during theprocedure, discomfort during recovery, and the overall recovery timeremain issues of importance. Thus, there exists a need for thoracicaccess ports which minimize post operative patient pain while enablingatraumatic retraction of tissue and which do not restrict access to thebody cavity, as well as facilitate retrieval of tissue specimens fromthe body cavity.

SUMMARY

In accordance with one aspect of the present disclosure, a surgicalaccess assembly for positioning within an opening in tissue is provided.The surgical access assembly comprises an outer member positionableoutside a patient and defining an opening therein to receive a surgicalinstrument therethrough. The outer member includes first and secondportions, at least one of the first and second portions movable withrespect to the other portion. The access assembly further includes aninner member positionable within a patient and a flexible memberextending between the inner member and outer member and operativelyassociated with the outer member. A locking mechanism locks the outermember in a plurality of select expanded positions, wherein movement ofone of the first and second portions adjusts tension on the flexiblemember to retract tissue. The locking mechanism includes firstengagement structure on the first portion engageable with the secondportion and a slidable member movable to a locking position to retainthe first and second portions in the select expanded position.

In some embodiments, the outer member is substantially rectangular inconfiguration. The access assembly in some embodiments includes a nerveprotecting member extending from the inner member, the nerve protectingmember extending in a direction toward the outer member.

In one embodiment, the engagement structure includes a substantiallyrigid projecting member having a sharp tip embeddable within a softermaterial. In an alternate embodiment, the engagement structure comprisesa first textured surface on the first portion engageable with a secondtextured surface on the second portion. In another alternate embodiment,the engagement structure includes a first set of projections formed onthe first portion and engageable with a second set of projections formedon the second portion, and the second set of projections can be out ofphase with the first set of projections. In another alternateembodiment, the engagement structure includes a row of raised bars.

In some embodiments, the engagement structure is biased to anon-engaging position and the slidable member moves the engagementstructure to an engaged position.

In some embodiments, the slidable member of the locking mechanismincludes first and second collars connected by a bridge.

In some embodiments, a pivoting arm is provided having a detentpositioned thereon, the slidable member biasing the pivoting arm to anengaged position when the slidable member is moved to the lockingposition.

In another aspect of the present disclosure, a surgical access assemblyfor positioning within an opening in tissue is provided. The surgicalaccess assembly comprises an outer member having an opening dimensionedand configured to receive a surgical instrument therethrough andincluding first and second portions, at least one of the first andsecond portions being movable relative to the second portion. The firstportion has a first engagement structure and the second portion has asecond engagement structure. A flexible member extends distally withrespect to the outer member, the flexible member being spread uponmovement of the first portion away from the second portion to retractsoft tissue adjacent the opening in tissue. A locking or retentionmechanism retains the first and second portions of the outer member in aplurality of spread positions, the locking mechanism having a firstposition wherein the first engagement structure is out of lockingengagement with the locking second engagement structure and a secondposition wherein the first engagement structure is in locking engagementwith the second engagement structure to retain the first and secondportions in a select spread position.

In some embodiments, the first engagement structure extends from apivoting arm normally biased to a non-engaged position.

In some embodiments, the locking mechanism includes a memberpositionable over the first and second engagement structures to lock thefirst and second portions in a select spread position.

In some embodiments, the first engagement structure is positioned onfirst and second sides of the first portion and the second engagementstructure is positioned on third and fourth sides of the second portion,and the locking mechanism includes first and second collars joined by abridge member, the first collar slidable over the engagement structureson the first and third sides and the second collar slidable over theengagement structures on the second and fourth sides.

The present disclosure also provides in another aspect a method ofaccessing an internal cavity of a patient comprising the steps of:

forming an opening in a patient's tissue;

providing an access assembly including:

-   -   an outer member positionable outside a patient and defining an        opening therein, the outer member including first and second        portions, the first portion movable with respect to the second        portion to adjust the opening, the opening dimensioned to        receive a surgical instrument therethrough;    -   an inner member positionable within a patient; and    -   a flexible member extending between the inner member and outer        member and operatively associated with the outer member, the        flexible member having a passageway to receive a surgical        instrument therethrough, wherein movement of the first portion        of the outer member adjusts a tension on the flexible member;

inserting the inner member of the access assembly through the opening intissue within an intercostal space of the patient and the flexiblemember extending proximally through the opening in tissue;

moving the first portion of the outer member to a select unlocked spreadposition to enlarge the opening in tissue and the passageway through theflexible member; and

subsequently moving a locking member to lock the first portion in theselect spread position.

The method may further comprise the step of introducing at least one ofsurgical instrumentation and tissue specimen through the passageway andopening in the tissue. In preferred embodiments, the first and secondportions frictionally engage when the locking member is moved to lockthe first portion.

The method can further include the step of folding the inner member forinsertion within the intercostal space into an internal cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the subject access port are described herein withreference to the drawings wherein:

FIG. 1 is a perspective view of one embodiment of the access port of thepresent disclosure;

FIG. 1A is a perspective view of an alternate embodiment of the accessport of the present disclosure;

FIG. 2 is front view illustrating a patient's skeletal structure withthe surgical access port of FIG. 1 positioned within the intercostalspace defined between adjacent ribs in accordance with the presentdisclosure;

FIG. 3 is an exploded perspective view of the access port of FIG. 1;

FIG. 4 is a cross-sectional view of one embodiment of the lockingmechanism of the present disclosure shown in the unlocked position;

FIG. 4A is a cross-sectional view similar to FIG. 4 showing the lockingmechanism in the locked position (taken along line 4A-4A of FIG. 1);

FIG. 5 is a view similar to FIG. 4 showing an alternate embodiment ofthe locking mechanism;

FIG. 6 is an exploded perspective view of another alternate embodimentof the locking mechanism of the present disclosure;

FIG. 7 is a cross-sectional view of the locking mechanism of FIG. 6shown in the unlocked position;

FIG. 7A is a cross-sectional view similar to FIG. 7 showing the lockingmechanism in the locked position;

FIG. 8 is an exploded perspective view of another alternate embodimentof the locking mechanism of the present disclosure;

FIG. 9 is a cross-sectional view of the locking mechanism of FIG. 8shown in the unlocked position;

FIG. 9A is a cross-sectional view similar to FIG. 9 showing the lockingmechanism in the locked position;

FIG. 10 is an exploded perspective view of yet another alternateembodiment of the locking mechanism of the present disclosure;

FIG. 11 is a cross-sectional view of the locking mechanism of FIG. 10shown in the unlocked position;

FIG. 11A is a cross-sectional view similar to FIG. 11 showing thelocking mechanism in the locked position;

FIG. 12 is an exploded perspective view of another alternate embodimentof the locking mechanism of the present disclosure;

FIG. 13 is a cross-sectional view of the locking mechanism of FIG. 12shown in the unlocked position; and

FIG. 13A is a cross-sectional view similar to FIG. 13 showing thelocking mechanism in the locked position.

DETAILED DESCRIPTION

Various embodiments of the presently disclosed access assembly, oraccess port, and methods of using the same, will now be described indetail with reference to the drawings wherein like references numeralsidentify similar or identical elements. In the drawings, and in thefollowing description, the term “proximal” refers to the end of theaccess port, or component thereof, that is closer to the clinician andthe term “distal” refers to the end that is further from the clinician,as is traditional and conventional in the art. It should be also beunderstood that the term “minimally invasive procedure” is intended toinclude surgical procedures through small openings/incisions performedwithin a confined space such as the thoracic cavity. Note the use of theterms upper and lower are with reference to the orientation shown in theFigures.

Referring now to FIGS. 1 and 3, a first embodiment of the presentlydisclosed surgical access port, generally identified by the referencenumeral 100, is depicted as a thoracic port 100 that is configured anddimensioned for insertion into the intercostal space located between theadjacent ribs “R” (FIG. 2) of a patient in order to allow for theinsertion and manipulation of one or more surgical instruments withinthe thoracic cavity. However, it is also envisioned that access port 100may be configured and dimensioned to provide access to a variety ofother internal body cavities and/or tissues. Access port 100 may beformed from any suitable biocompatible material of strength suitable forthe purpose described herein, including, but not being limited to,polymeric materials.

The access port 100 is configured and dimensioned to extend into a bodycavity, e.g., the thoracic cavity “T” (FIG. 2), through the intercostalspace, and generally includes an outer or proximal frame or member 110having first and second portions 112, 114. A flexible member, e.g.membrane 170, is coupled to frame 110 and extends distally therefrom.The distal end of the flexible member 170 is attached to an inner ordistal frame (or member) 150. The outer frame 110 is movable betweenvarious spread positions to widen the passageway for insertion ofinstrumentation. More specifically, portions 112 and 114 of frame 110are relatively slidable to increase the distance between respective endwalls 113, 115, and to increase the size of the opening 117 in the frame110. The sliding of portions 112 and 114 applies tension to the flexiblemember 170 to retract tissue adjacent the incision in the patient towiden the access opening in the manner described below. It should beappreciated that although as described below both the first and secondportions 112, 114 are slidable, it is also contemplated that only thefirst portion 112 (or lower portion as viewed in the orientation ofFIG. 1) is slidable with respect to the second (upper) portion 114, orthat only the second portion 114 (the upper portion as viewed in theorientation of FIG. 1) is slidable with respect to the first (lower)portion 112.

As shown, the outer frame 110 is substantially rectangular in shape witha substantially rectangular opening. As can be appreciated, other shapeframes and openings are also contemplated. Note also that preferably theshape is elongated, e.g. has a length greater than its width.

Inner member 150 has an elongated opening 155 therethrough for passageof surgical instrumentation. The member 150 also has a nerve protectingwall or lip 152 extending along the opening 155, and preferablysubstantially surrounding the opening. Lip 152 extends upwardly towardouter frame 110. The member 150 is preferably composed of asubstantially rigid material to provide anchoring of the access portwhile of sufficient flexibility to be bent or reconfigured for insertionas described below.

Flexible membrane 170 is generally funnel shaped, is coupled at itsdistal end 174 to lip 152 of inner member 150 and extends proximallytherefrom. Proximal end 172 of flexible membrane 170 is coupled to endwalls 113, 115 to isolate tissue surrounding access port 100 from thepassageway 190 extending therethrough, thus reducing the risk of tissuedamage and/or infection during the surgical procedure. It can beattached by various methods such as welding or gluing. It is envisionedthat flexible membrane 170 is configured for soft tissue retraction. Itis also envisioned that flexible membrane 170 can be of sufficientelasticity to permit retraction of a wide range of tissue thicknessessince there may be a wide range of tissue thicknesses among differentpatients. It is also envisioned that flexible membrane 170 is ofsufficient strength to prevent accidental tearing and/or puncture bysurgical instrumentation inserted through access port 100. Additionally,it is envisioned that flexible membrane 170 be made from abio-compatible material to reduce the incidents of adverse reaction by apatient upon contact with the patient's tissue. Flexible membrane 170may also be made of a transparent material to allow the surgeon tobetter visualize the surgical site and surrounding tissue.

Outer frame 110 is preferably sufficiently rigid to retain membrane 170in a tensioned configuration. As frame 110 is expanded (spread) in thedirection of the arrow of FIG. 1, membrane 170 is tensioned andstretched radially outwardly to retract tissue and/or to expand thepassageway 190 extending through membrane 170.

Several alternate embodiments of a locking mechanism for outer frame 110are disclosed herein. Each of the locking mechanisms includes a firstengagement structure on the first portion and a second engagementstructure on the second portion of the outer frame and a slidablelocking member which locks the first and second portions in the selectedspread position. In this manner, the first and second portions of theouter frame are moved apart to a desired spread position to expand andstretch the flexible membrane 170 and then retained or locked in theselect position. Such engagement structure is preferably positioned onboth sides of the frame 110.

The locking mechanism of FIG. 4 will first be described. This lockingmechanism is shown in conjunction with FIG. 1, it being understood thatthe various locking mechanisms described herein can be utilized with theaccess port of FIG. 1 or the access port of FIG. 1A. Note thatpreferably there are two locking mechanisms in each of the lockingmechanism embodiments disclosed herein, one on each side of the frame110 as shown in FIGS. 1 and 3 and described below.

In the embodiment of FIG. 4, locking mechanism 160 includes a firstpivoting locking arm 162 positioned on a first side of the secondportion 114. The arm 162 can be formed integrally with the secondportion, e.g. similar to an integral tab formed for example by a cutoutin the second portion 114. Alternatively, the arm 162 can be a separateelement attached to the second portion such as shown in FIG. 5 wherepivoting arm 162′ is attached by pin 163 to frame portion 114′ andcammed by sliding collar 167′. Other attachment methods can also beutilized.

A second pivoting locking arm 162 a (see FIG. 1) identical to lockingarm 162 is provided on the opposing side of portion 114 and functions inthe same manner as locking arm 162.

The pivoting arm 162 (and 162 a) is preferably biased to a position awayfrom the second portion 112 so in its normal position its lower surface165 does not engage the first portion 112. That is, in the orientationof FIGS. 1 and 4, it is spring biased upwardly. Arm 162 includes aramped surface 168 for engagement by a locking collar described below.It is also contemplated that in its normal position the lower surface ofthe arm 162 (and 162 a) it can be slightly engaged with the firstportion 112, but not sufficiently engaged to lock the first and secondportions 112, 114 or restrict movement.

In the FIG. 4 embodiment, a sharp pointed tip 164, preferably composedof metal, extends from lower surface 165 of arm 162 to provide anengagement structure. The lower portion 112 of frame 110 is composed ofa material, at least on its upper surface 118, to enable reception ofthe tip 164. That is, when pivoting arm 162 is forced by sliding collarmember 167 into engagement with lower portion 112, tip 164 digs into thesoft material engagement structure on upper surface 118 and becomesembedded therein, thus helping to retain the two engagement structures.This restricts movement of the upper and lower portions 114, 112. Thus,in use, once the desired spread position of the lower portion 112 andupper portion 114 is achieved to tension membrane 170 and retracttissue, sliding member or collar 167 is slid in the direction of thearrow to pivot arm 162 into engagement with lower portion 112. Thislocking position of arm 162 is shown in FIG. 4A. Locking arm 162 apreferably has an identical sharp pointed tip and functions in theidentical fashion as locking arm 162, i.e. embeds in the soft materialof lower portion 112 when collar 167 a, identical to collar 167, is slidover arm 162 a. The collars 167, 167 a maintain the engagementstructures in their locking position.

In a preferred embodiment, the first and second collars 167, 167 a aresubstantially identical and each have an opening 169, 169 a for slidingreception of the frame 114. Other configurations of collars then thatshown in the various embodiments herein are also contemplated as long asit achieves its function of movement to clamp the respective pivotingarm 162, 162 a into locking arrangement.

In the embodiment of FIG. 1, two separate collars are provided which areindependently movable. However, it is also contemplated that the twocollars can be connected such that they both can be moved simultaneouslyand in a single movement by the surgeon. This variation is shown in FIG.1A. The components of FIG. 1A are substantially identical to those ofFIG. 1, except for the collars, and have the same reference numeralsexcept are numbered in the “200 series.” Therefore, access port 200 hasan outer frame or member 210 with pivoting locking arms 262, 262 a, aflexible membrane 270 and an inner frame or member 250, etc. For clarityand brevity, further details of these components are not described ordesignated in FIG. 1A since they are the same as those of FIG. 1.

The difference between FIG. 1 and FIG. 1A is the slidable locking collar290. As shown, first slidable locking collar 290 is positioned on oneside of frame 210 and a second slidable locking collar 291 is positionedon a second side of frame 210. A bridge 292 connects the two collars290, 291 and extends across the opening 217 in frame 210, preferablyspaced from the center of the opening 217 so as not to interfere withthe passage of surgical instrumentation therethrough. After the firstand second portions 212, 214 of frame 210 are spread to the selectposition in the same manner as in the embodiments of FIG. 1 to tensionmembrane 270, the bridge can be moved (pulled toward wall 215 in theembodiment of FIG. 1A) to move the collars 290, 291 in the direction ofthe arrow to cam the pivoting arms 262, 262 a downwardly into engagementwith the upper surface of lower portion 212 to retain the portions 212,214 in the select position in the same manner as in FIG. 1. It should beappreciated that any of the locking mechanisms and engagement structuresdisclosed herein can be utilized with the bridged collars of FIG. 1A.

It should also be appreciated that although the collars 290, 291 arepulled to lock portions 112, 114 because of their initial position(between arms 262, 262 a and wall 213), it is also contemplated that intheir initial position the collars can be on the other side of pivotingarms 262, 262 a, i.e. closer to the wall 215. In this version, thebridge 291 would be pushed in a direction away from wall 215 to rideover and cam arms 262, 262 a into engagement with lower portion 212 tolock the frame portions 212, 214 in a select position.

Turning now to other alternate embodiments, and turning first to FIGS.8-9, the access port differs from access port 100 of FIG. 1 in theengagement structures of the locking mechanisms. Otherwise, the portsare identical.

Pivoting locking arm 362 has a bottom surface 365 with an engagementstructure in the form of a textured surface 383, preferably moldedthereon. A second engagement structure in the form of a high frictiontextured surface 319 is preferably molded onto the top surface 318 oflower portion 314 (as viewed in the orientation of FIG. 8). Othermethods of providing a textured surface are also contemplated. Differenttypes of textured surfaces can be utilized such as beads, ridges, domesand/or points which interlock with a textured surface of lower portion312. A second locking arm identical to locking arm 362 is provided onthe other side of upper portion 314 and operates in the same fashion.Sliding collar 367 contacts ramped surface 368 of pivoting arm 362 tobias textured surface 383 into locking engagement with textured surface319. Another sliding collar identical to collar 367 contacts the otherlocking arm in the same manner. This movement of the collars locks theupper and lower portions 314, 312 in the same manner as the collars 167,167 a of FIG. 1.

In the alternate embodiment of FIG. 6, the access port differs fromaccess port 100 of FIG. 1 in the engagement structures. Otherwise, theports are identical. Locking mechanism 460 includes a first pivotinglocking arm 462 and a second pivoting locking arm (not shown), eachbiased away from the lower frame portion 412 (as viewed in theorientation of FIG. 6) in the same manner as described above withrespect to the locking arms 162, 162 a of FIG. 1. As in the embodimentof FIG. 4, as well as the other embodiments herein, the first pivotingarm 462 (and second arm) can be a separate component attached to theupper frame portion 414 by a pin 463 as shown or by other methods, oralternately formed integrally with the frame 414.

Locking arm 462 includes a bottom surface 465 with two detents 464 a,464 b. These detents 464 a, 464 b are configured and dimensioned to bereceived in locking engagement within two of the plurality of recesses466 (only a few are labeled for clarity) in the bottom portion 412. Notethe number of recesses 466 preferably exceeds the number of detents 464a, 464 b to enable locking in a number of different select positions ofthe frame portion 412, 414. It should be appreciated that the number ofdetents and recesses can be different than that shown.

A second locking arm (not shown), identical to locking arm 462, ispositioned on the other side of the second (upper) portion 414. As withlocking arm 462, the second locking arm has two (or more) detentsengageable with two of the recesses on a second side of the secondportion 412, depending on the relative position of the first and secondportions.

A locking member in the form of a sliding collar 467 is slid over theramped surface 468 of arm 462 to force it downwardly against its normalbias into engagement with the recesses 466. Thus, in use, afterspreading the lower and upper portions 412, 414 to the desired positionto tension the membrane and retract tissue around the incision in thesame manner as in the embodiment of FIG. 1 (and/or FIG. 1A), the surgeonslides first collar 467 (and the second collar) over the respectivepivoting arm 462, resulting in engagement of the decent engagementstructure with the recess engagement structure. The second slidingcollar operates in the same fashion as collar 467 to pivot therespective arm to provide engagement of the detents of this arm with theunderlying recesses. Note if at the desired spread position the detentsare not in exact alignment with a recess, the upper and/or lower portion414, 412 can slide slightly until the detents on both sides of the upperportion 414 are aligned with the recesses on the lower portion 412. Asnoted above, with the exception of the locking mechanism 460, thisembodiment is identical to that of FIG. 1.

FIGS. 10 and 11 illustrate an alternate embodiment of the lockingmechanism, designated generally by reference numeral 560 which can beutilized with the access ports of FIGS. 1 and 1A. That is, the accessport of FIG. 10 is identical to the access port 100 of FIG. 1 except forthe locking mechanism. More specifically, locking mechanism 560 has aplurality of projections, e.g. domes or balls 561 on an upper surface ofthe lower portion 512 and a plurality of projections, e.g. domes orballs 569, on the lower surface 565 of the pivoting locking arm 562.Although the arm 562 is shown integral, as in the other embodimentsdisclosed herein, it could alternatively be a separate componentattached to the upper portion. Only a few of the domes/balls are labeledfor clarity.

In the illustrated embodiment, two rows of domes 569 are positioned onpivoting arm 562 of frame portion 514. Preferably, a greater number ofrows of similar configured domes/balls 561 are positioned on lowerportion 512. When the collar 567 is slid in the direction of the arrowof FIG. 11A, the ramp 568 of arm 562 is engaged to cam arm 562downwardly against its normal bias so the domes 569 (engagementstructure) move from a non-engaged to an engaged position to engage thedome engagement structure on lower portion 512. Note the domes 569 arepreferably configured and dimensioned to fit within the space betweendomes 561. This is shown in FIG. 11A.

A second pivoting arm (not shown) identical to pivoting arm 562 isprovided on the other side of the outer frame portion 514 tofrictionally engage a corresponding series of projections, e.g.domes/balls (not shown) identical to domes 561 upon movement of a secondcollar (not shown) identical to collar 567. Thus, as in the embodimentsof FIGS. 6 and 8, the engagement structure provides retention of theframe portions in the select spread positions. Such engagement isretained by the collars.

It should be appreciated that a different number of balls/domes can beprovided in order to achieve retention of the dome structures.

In the alternate embodiment of FIG. 12, the locking mechanism,designated generally by reference numeral 660, is shown which can beutilized with the access ports of FIGS. 1 and 1A. That is, the accessport of FIG. 12 is identical to the access port 100 of FIG. 1 except forthe locking mechanism. More specifically, locking mechanism 660 has aplurality of transversely extending bars 664 on the upper surface oflower portion 612 and a plurality of similar transverse bars 664 on thelower surface 665 of the pivoting locking arm 662. Although the arm 662is shown integral, as in the other embodiments disclosed herein, itcould alternatively be a separate component attached to the upperportion. Only a few of the bars are labeled for clarity.

In the illustrated embodiment, two bars 669 are positioned on pivotingarm 662 of frame portion 614. Preferably, a greater number of bars 664are positioned on lower portion 612. When the collar 667 is slid in thedirection of the arrow of FIG. 13A, the ramp 668 of arm 662 is engagedto cam arm 662 downwardly against its normal bias so the bars 669(engagement structure) move from a non-engaged to an engaged position toengage bar engagement structure on lower portion 612. That is, the bars669 are moved into the space between bars 664 as shown in FIG. 13A.

A second pivoting arm (not shown) identical to pivoting arm 662 isprovided on the other side of the upper frame portion 614 to engage bars(not shown) identical to bars 664 positioned on the other side of lowerframe portion 612 upon movement of a second collar (not shown) identicalto collar 667.

The use of the access port will now be described in conjunction with theembodiment of FIG. 1, it being understood that the embodiment of FIG. 1Awould work in a similar fashion (except for the simultaneous movement ofthe collars by the bridge) and the other locking mechanisms of FIGS.6-13 would also function in a similar fashion to FIG. 1, the differencebeing the differing engagement structures of the lower surface of thepivoting arm and the upper surface of the lower outer frame portion.

The use of the access port is described for thoracic surgery, it beingunderstood that it can be utilized in other minimally invasiveprocedures.

Initially, an opening, or incision, is made in the patient's outertissue wall of the thoracic body cavity by conventional means. Theincision is made between adjacent ribs “R” (FIG. 2), extending along theintercostal space, and is relatively narrow and elongated.

For insertion through the incision, the inner member 150 is bent orreconfigured to reduce its transverse dimension for insertion throughthe patient's incision and into the body cavity. Note different sizes ofaccess ports can also be used to accommodate different patients.

With access port 100 in the placement position, the inner frame (member)150 is positioned within the body cavity adjacent the inner portion ofthe incision, flexible membrane 170 extends through the incision tooutside the patient's body, and outer frame (member) 110 rests on thepatient's skin. The outer frame 110 can now be expanded (see FIG. 2).Note the longitudinal axis of the inner frame 150 is substantiallyparallel to a long axis of the incision and the longitudinal axis ofouter frame 110 is substantially transverse to a long axis of theincision, the longitudinal axis defining the length of the respectiveframe which exceeds its width.

In the initial position of access port 100, flexible member, e.g.membrane 170, defines a funnel shape with outer frame 110 retainingproximal end 172 of flexible membrane 170 while distal end 174 offlexible membrane 170 defines a smaller diameter due to the engagementof distal end 174 with the smaller inner frame 150. That is, since thewidth and length of outer member 110 is greater than the width andlength of inner member 150 to which the membrane 170 is attached at itsdistal end, a funnel shape is formed. In this initial position, lip 152of inner member 150, is configured to seat a rib “R” of a patienttherein to protect the rib “R,” the intercostal nerve, and surroundingtissue. That is, lip 152 extends upwardly into the opening in tissueadjacent the ribs “R,” i.e., within the thoracic cavity “T”. Additionalcushioning (not shown) may be provided to provide further protection toribs “R” and to surrounding tissue. Outward flexion of flexible membrane170 expands the intercostal space, thus maximizing passageway 190, andgiving access port 100 the maximum length.

In use, to spread the first and second portions or sections 112 and 114of outer frame 110 to stretch (radially tension) the flexible membrane170 to retract tissue adjacent the ribs and incision and widen theincision passageway 190 for instrumentation, the end wall 115 of thesecond portion 114 and the end wall 113 of the first portion 112 aregrasped by the surgeon and pulled away from each other, therebyexpanding the distance between end walls 113 and 115. Note the tissue isspread transverse to the long axis of the incision. When the desiredspread position, i.e. desired tissue retraction, is achieved, thesurgeon slides locking collar 167 along frame 110 and over the pivotingarm 162 (see FIG. 4A) and locking collar 167 a along frame 110 and overpivoting arm 162 a, forcing the arms 162, 162 a to pivot toward thefirst (lower) portion 112 such that the engagement surfaces are movedfrom a non-engaged position to an engaged position to lock (secure) theupper and lower portions 114, 112 in the select position. Thisengagement of the engagement structures enhances the securement of thetwo portions 112 and 114 by limiting slippage as the locking collars167, 167 a clamp the two portions 112, 114 against movement. (In theembodiment of FIG. 1A the surgeon can slide the bridge 292 to move bothlocking collars together as described above). As noted above, thelocking collars of the other embodiments described herein function in asimilar manner to clamp the upper frame portions against movement as thevarious engagement structures are engaged.

With access port 100 secured in the desired expanded position, surgicalinstrumentation may be inserted through opening 170, passageway 190, andopening 155 to perform the surgical procedure within the body cavity.The low-profile configuration of access port 100, along the externalsurface of tissue, allows for greater access to the thoracic cavity “T”and for greater manipulation of instrumentation disposed throughpassageway 190.

Note that in the embodiments described herein, the engagement structurescan be configured to provide sufficient frictional engagement torestrict movement, with the collars securely locking the engagementstructures, or alternatively, configured to slightly frictionally engagewith a slight retention force and mostly to prevent slippage, relyingmainly on the collars to restrict any movement.

Upon completion of the surgical procedure, locking collars 167, 167 aare moved toward their original position, to release the pivoting arms162 and 162 a to allow them to move to their unlocked non-engagedposition, thereby allowing the frame portions 110, 112 to be movedtoward each other toward their initial position to untension flexiblemembrane 170. Next, the surgeon may grasp inner member 150 to fold orreconfigure it to reduce its transverse dimension to remove it from thebody cavity and through the incision.

As will be appreciated, access port 100 is easily inserted, manipulated,and removed from a patient's body. Further, the access port 100 isminimally intrusive, flexible to conform to a patient's anatomy, andprovides good visibility into the thoracic cavity “T” (FIG. 3).Additionally, the low-profile configuration of access port 100 isparticularly advantageous, for example, in the removal, or retrieval, oftissue specimens from within the body.

The flexible membrane 170 may be coated with a lubricant, or gel, to aidin the insertion and removal of surgical instrumentation and/or tissuespecimens from access port 100.

In the embodiments described herein, the pivoting arms move from a“non-engaged” to an “engaged” position by the sliding collar. It shouldbe appreciated that such “non-engaged” position can include a“non-locking” position wherein the engagement structures are in partialengagement, e.g. in contact, but not yet in full engagement, and thenthey would be moved by the collars to an engaged retention positionwhere movement would be restricted.

Although described for use in thoracic procedures, it should also beunderstood that the access ports described herein can be used in otherminimally invasive surgical procedures.

Persons skilled in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merelyexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beeffected by one skilled in the art without departing from the scope orspirit of the disclosure. Additionally, it is envisioned that theelements and features illustrated or described in connection with oneexemplary embodiment may be combined with the elements and features ofanother without departing from the scope of the present disclosure, andthat such modifications and variations are also intended to be includedwithin the scope of the present disclosure. Accordingly, the subjectmatter of the present disclosure is not to be limited by what has beenparticularly shown and described, except as indicated by the appendedclaims.

What is claimed is:
 1. A method of accessing an internal cavity of apatient comprising: forming an opening in a patient's tissue; providingan access assembly including: an outer member positionable outside thepatient and defining an opening therein dimensioned to receive asurgical instrument, the outer member including first and secondportions, the first and second portions being relatively movable toadjust a dimension of the opening; an inner member configured anddimensioned for insertion through the opening in the patient's tissue; aflexible member extending between the inner member and the outer memberand operatively associated with the outer member, the flexible memberdefining a passageway configured and dimensioned to receive the surgicalinstrument, wherein relative movement between the first and secondportions of the outer member adjusts tension on the flexible member; anda first locking member including a first arm; inserting the inner memberinto the opening in the patient's tissue such that the inner member ispassed into an intercostal space defined between the patient's adjacentribs such that the flexible member extends proximally through theopening in the patient's tissue; enlarging the opening in the patient'stissue and the passageway through the flexible member by effectingrelative movement between the first and second portions of the outermember; and subsequently actuating the first locking member to lock theouter member in one of a plurality of select expanded positions byembedding a tip of the first arm in a soft material of the outer member.2. The method according to claim 1, further including passing thesurgical instrument and/or a tissue specimen through the passagewayextending through the flexible member and the opening in the patient'stissue.
 3. The method of claim 1, wherein inserting the inner memberinto the opening in the patient's tissue includes folding the innermember.
 4. The method of claim 1, wherein actuating the first lockingmember includes sliding a first collar in relation to the outer memberto embed the tip of the first arm in the soft material of the outermember.
 5. The method of claim 4, wherein sliding the first collar inrelation to the outer member includes contacting a ramped surface of thefirst arm with the first collar to cam the first arm towards the softmaterial of the outer member.
 6. The method of claim 5, whereinproviding the access assembly includes providing a second locking memberincluding a second arm.
 7. The method of claim 6 further includingactuating the second locking member to lock the outer member in one ofthe plurality of select expanded positions by embedding a tip of thesecond arm in the soft material of the outer member.
 8. The method ofclaim 7, wherein actuating the second locking member includes sliding asecond collar in relation to the outer member to embed the tip of thesecond arm in the soft material of the outer member.
 9. The method ofclaim 8, wherein sliding the second collar in relation to the outermember includes contacting a ramped surface of the second arm with thesecond collar to cam the second arm towards the soft material of theouter member.
 10. A method of accessing an internal workspacecomprising: inserting an access assembly into an opening in tissue suchthat an inner member of the access assembly is positioned beneath thetissue, an outer member of the access assembly is positioned above thetissue, and a flexible member connecting the inner and outer membersextends through the opening in the tissue; moving the outer member intoan expanded configuration to enlarge the opening in the tissue byeffecting relative movement between first and second portions of theouter member; actuating a locking mechanism of the access assembly tolock the outer member in the expanded configuration by embedding aportion of the locking mechanism in a portion of the outer member; andintroducing at least one surgical instrument into the internal workspacethrough a passageway defined by the flexible member.
 11. The method ofclaim 10, wherein moving the outer member into the expandedconfiguration applies tension to the flexible member.
 12. The method ofclaim 10, wherein actuating the locking mechanism includes pivoting afirst arm of the locking mechanism towards the outer member.
 13. Themethod of claim 12, wherein actuating the locking mechanism furtherincludes embedding a tip of the first arm in a soft material of theouter member.
 14. The method of claim 13, wherein actuating the lockingmechanism includes sliding a first collar in relation to the outermember such that the first collar contacts a ramped surface of the firstarm to cam the first arm towards the soft material of the outer member.15. The method of claim 14, wherein actuating the locking mechanismfurther includes pivoting a second arm of the locking mechanism towardsthe outer member.
 16. The method of claim 15, wherein actuating thelocking mechanism further includes embedding a tip of the second arm inthe soft material of the outer member.
 17. The method of claim 16,wherein actuating the locking mechanism further includes sliding asecond collar in relation to the outer member such that the secondcollar contacts a ramped surface of the second arm to cam the second armtowards the soft material of the outer member.